// __ _____ _____ _____ // __| | __| | | | JSON for Modern C++ (supporting code) // | | |__ | | | | | | version 3.12.0 // |_____|_____|_____|_|___| https://github.com/nlohmann/json // // SPDX-FileCopyrightText: 2013 - 2025 Niels Lohmann // SPDX-License-Identifier: MIT #include #include #include "doctest_compatibility.h" #include using nlohmann::json; namespace persons { class person_with_private_data { private: std::string name{}; // NOLINT(readability-redundant-member-init) int age = 0; json metadata = nullptr; public: bool operator==(const person_with_private_data& rhs) const { return name == rhs.name && age == rhs.age && metadata == rhs.metadata; } person_with_private_data() = default; person_with_private_data(std::string name_, int age_, json metadata_) : name(std::move(name_)) , age(age_) , metadata(std::move(metadata_)) {} NLOHMANN_DEFINE_TYPE_INTRUSIVE(person_with_private_data, age, name, metadata) }; class derived_person_with_private_data : public person_with_private_data { private: std::string hair_color{"blue"}; public: bool operator==(const derived_person_with_private_data& rhs) const { return person_with_private_data::operator==(rhs) && hair_color == rhs.hair_color; } derived_person_with_private_data() = default; derived_person_with_private_data(std::string name_, int age_, json metadata_, std::string hair_color_) : person_with_private_data(std::move(name_), age_, std::move(metadata_)) , hair_color(std::move(hair_color_)) {} NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE(derived_person_with_private_data, person_with_private_data, hair_color) }; class person_with_private_data_2 { private: std::string name{}; // NOLINT(readability-redundant-member-init) int age = 0; json metadata = nullptr; public: bool operator==(const person_with_private_data_2& rhs) const { return name == rhs.name && age == rhs.age && metadata == rhs.metadata; } person_with_private_data_2() = default; person_with_private_data_2(std::string name_, int age_, json metadata_) : name(std::move(name_)) , age(age_) , metadata(std::move(metadata_)) {} std::string getName() const { return name; } int getAge() const { return age; } json getMetadata() const { return metadata; } NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT(person_with_private_data_2, age, name, metadata) }; class derived_person_with_private_data_2 : public person_with_private_data_2 { private: std::string hair_color{"blue"}; public: bool operator==(const derived_person_with_private_data_2& rhs) const { return person_with_private_data_2::operator==(rhs) && hair_color == rhs.hair_color; } derived_person_with_private_data_2() = default; derived_person_with_private_data_2(std::string name_, int age_, json metadata_, std::string hair_color_) : person_with_private_data_2(std::move(name_), age_, std::move(metadata_)) , hair_color(std::move(hair_color_)) {} std::string getHairColor() const { return hair_color; } NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_WITH_DEFAULT(derived_person_with_private_data_2, person_with_private_data_2, hair_color) }; class person_without_private_data_1 { public: std::string name{}; // NOLINT(readability-redundant-member-init) int age = 0; json metadata = nullptr; bool operator==(const person_without_private_data_1& rhs) const { return name == rhs.name && age == rhs.age && metadata == rhs.metadata; } person_without_private_data_1() = default; person_without_private_data_1(std::string name_, int age_, json metadata_) : name(std::move(name_)) , age(age_) , metadata(std::move(metadata_)) {} NLOHMANN_DEFINE_TYPE_INTRUSIVE(person_without_private_data_1, age, name, metadata) }; class derived_person_without_private_data_1 : public person_without_private_data_1 { public: std::string hair_color{"blue"}; public: bool operator==(const derived_person_without_private_data_1& rhs) const { return person_without_private_data_1::operator==(rhs) && hair_color == rhs.hair_color; } derived_person_without_private_data_1() = default; derived_person_without_private_data_1(std::string name_, int age_, json metadata_, std::string hair_color_) : person_without_private_data_1(std::move(name_), age_, std::move(metadata_)) , hair_color(std::move(hair_color_)) {} NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE(derived_person_without_private_data_1, person_without_private_data_1, hair_color) }; class person_without_private_data_2 { public: std::string name{}; // NOLINT(readability-redundant-member-init) int age = 0; json metadata = nullptr; bool operator==(const person_without_private_data_2& rhs) const { return name == rhs.name && age == rhs.age && metadata == rhs.metadata; } person_without_private_data_2() = default; person_without_private_data_2(std::string name_, int age_, json metadata_) : name(std::move(name_)) , age(age_) , metadata(std::move(metadata_)) {} }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(person_without_private_data_2, age, name, metadata) class derived_person_without_private_data_2 : public person_without_private_data_2 { public: std::string hair_color{"blue"}; public: bool operator==(const derived_person_without_private_data_2& rhs) const { return person_without_private_data_2::operator==(rhs) && hair_color == rhs.hair_color; } derived_person_without_private_data_2() = default; derived_person_without_private_data_2(std::string name_, int age_, json metadata_, std::string hair_color_) : person_without_private_data_2(std::move(name_), age_, std::move(metadata_)) , hair_color(std::move(hair_color_)) {} }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE(derived_person_without_private_data_2, person_without_private_data_2, hair_color) class person_without_private_data_3 { public: std::string name{}; // NOLINT(readability-redundant-member-init) int age = 0; json metadata = nullptr; bool operator==(const person_without_private_data_3& rhs) const { return name == rhs.name && age == rhs.age && metadata == rhs.metadata; } person_without_private_data_3() = default; person_without_private_data_3(std::string name_, int age_, json metadata_) : name(std::move(name_)) , age(age_) , metadata(std::move(metadata_)) {} std::string getName() const { return name; } int getAge() const { return age; } json getMetadata() const { return metadata; } }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT(person_without_private_data_3, age, name, metadata) class derived_person_without_private_data_3 : public person_without_private_data_3 { public: std::string hair_color{"blue"}; public: bool operator==(const derived_person_without_private_data_3& rhs) const { return person_without_private_data_3::operator==(rhs) && hair_color == rhs.hair_color; } derived_person_without_private_data_3() = default; derived_person_without_private_data_3(std::string name_, int age_, json metadata_, std::string hair_color_) : person_without_private_data_3(std::move(name_), age_, std::move(metadata_)) , hair_color(std::move(hair_color_)) {} std::string getHairColor() const { return hair_color; } }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_WITH_DEFAULT(derived_person_without_private_data_3, person_without_private_data_3, hair_color) class person_with_private_alphabet { public: bool operator==(const person_with_private_alphabet& other) const { return a == other.a && b == other.b && c == other.c && d == other.d && e == other.e && f == other.f && g == other.g && h == other.h && i == other.i && j == other.j && k == other.k && l == other.l && m == other.m && n == other.n && o == other.o && p == other.p && q == other.q && r == other.r && s == other.s && t == other.t && u == other.u && v == other.v && w == other.w && x == other.x && y == other.y && z == other.z; } private: int a = 0; int b = 0; int c = 0; int d = 0; int e = 0; int f = 0; int g = 0; int h = 0; int i = 0; int j = 0; int k = 0; int l = 0; int m = 0; int n = 0; int o = 0; int p = 0; int q = 0; int r = 0; int s = 0; int t = 0; int u = 0; int v = 0; int w = 0; int x = 0; int y = 0; int z = 0; NLOHMANN_DEFINE_TYPE_INTRUSIVE(person_with_private_alphabet, a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z) }; class person_with_public_alphabet { public: bool operator==(const person_with_public_alphabet& other) const { return a == other.a && b == other.b && c == other.c && d == other.d && e == other.e && f == other.f && g == other.g && h == other.h && i == other.i && j == other.j && k == other.k && l == other.l && m == other.m && n == other.n && o == other.o && p == other.p && q == other.q && r == other.r && s == other.s && t == other.t && u == other.u && v == other.v && w == other.w && x == other.x && y == other.y && z == other.z; } int a = 0; int b = 0; int c = 0; int d = 0; int e = 0; int f = 0; int g = 0; int h = 0; int i = 0; int j = 0; int k = 0; int l = 0; int m = 0; int n = 0; int o = 0; int p = 0; int q = 0; int r = 0; int s = 0; int t = 0; int u = 0; int v = 0; int w = 0; int x = 0; int y = 0; int z = 0; }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(person_with_public_alphabet, a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z) class person_without_default_constructor_1 { public: std::string name; int age; bool operator==(const person_without_default_constructor_1& other) const { return name == other.name && age == other.age; } person_without_default_constructor_1(std::string name_, int age_) : name{std::move(name_)} , age{age_} {} NLOHMANN_DEFINE_TYPE_INTRUSIVE_ONLY_SERIALIZE(person_without_default_constructor_1, name, age) }; class person_without_default_constructor_2 { public: std::string name; int age; bool operator==(const person_without_default_constructor_2& other) const { return name == other.name && age == other.age; } person_without_default_constructor_2(std::string name_, int age_) : name{std::move(name_)} , age{age_} {} }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE(person_without_default_constructor_2, name, age) class derived_person_only_serialize_public : public person_without_default_constructor_1 { public: std::string hair_color; derived_person_only_serialize_public(std::string name_, int age_, std::string hair_color_) : person_without_default_constructor_1(std::move(name_), age_) , hair_color(std::move(hair_color_)) {} }; // NOLINTNEXTLINE(misc-use-internal-linkage) NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE(derived_person_only_serialize_public, person_without_default_constructor_1, hair_color) class derived_person_only_serialize_private : person_without_default_constructor_1 { private: std::string hair_color; public: derived_person_only_serialize_private(std::string name_, int age_, std::string hair_color_) : person_without_default_constructor_1(std::move(name_), age_) , hair_color(std::move(hair_color_)) {} NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_ONLY_SERIALIZE(derived_person_only_serialize_private, person_without_default_constructor_1, hair_color) }; } // namespace persons TEST_CASE_TEMPLATE("Serialization/deserialization via NLOHMANN_DEFINE_TYPE_INTRUSIVE and NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; constexpr bool is_ordered = std::is_same::value; SECTION("person") { // serialization T p1("Erik", 1, {{"haircuts", 2}}); CHECK(Json(p1).dump() == (is_ordered ? R"({"age":1,"name":"Erik","metadata":{"haircuts":2}})" : R"({"age":1,"metadata":{"haircuts":2},"name":"Erik"})")); // deserialization auto p2 = Json(p1).template get(); CHECK(p2 == p1); // roundtrip CHECK(T(Json(p1)) == p1); CHECK(Json(T(Json(p1))) == Json(p1)); // check exception in case of missing field Json j = Json(p1); j.erase("age"); CHECK_THROWS_WITH_AS(j.template get(), "[json.exception.out_of_range.403] key 'age' not found", typename Json::out_of_range); } } TEST_CASE_TEMPLATE("Serialization/deserialization via NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE and NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; constexpr bool is_ordered = std::is_same::value; SECTION("person") { // serialization T p1("Erik", 1, {{"haircuts", 2}}, "red"); CHECK(Json(p1).dump() == (is_ordered ? R"({"age":1,"name":"Erik","metadata":{"haircuts":2},"hair_color":"red"})" : R"({"age":1,"hair_color":"red","metadata":{"haircuts":2},"name":"Erik"})")); // deserialization auto p2 = Json(p1).template get(); CHECK(p2 == p1); // roundtrip CHECK(T(Json(p1)) == p1); CHECK(Json(T(Json(p1))) == Json(p1)); // check exception in case of missing field Json j = Json(p1); j.erase("age"); CHECK_THROWS_WITH_AS(j.template get(), "[json.exception.out_of_range.403] key 'age' not found", typename Json::out_of_range); } } TEST_CASE_TEMPLATE("Serialization/deserialization via NLOHMANN_DEFINE_TYPE_INTRUSIVE_WITH_DEFAULT and NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_WITH_DEFAULT", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; constexpr bool is_ordered = std::is_same::value; SECTION("person with default values") { // serialization of default constructed object const T p0{}; CHECK(Json(p0).dump() == (is_ordered ? R"({"age":0,"name":"","metadata":null})" : R"({"age":0,"metadata":null,"name":""})")); // serialization T p1("Erik", 1, {{"haircuts", 2}}); CHECK(Json(p1).dump() == (is_ordered ? R"({"age":1,"name":"Erik","metadata":{"haircuts":2}})" : R"({"age":1,"metadata":{"haircuts":2},"name":"Erik"})")); // deserialization auto p2 = Json(p1).template get(); CHECK(p2 == p1); // roundtrip CHECK(T(Json(p1)) == p1); CHECK(Json(T(Json(p1))) == Json(p1)); // check default value in case of missing field Json j = Json(p1); j.erase("name"); j.erase("age"); j.erase("metadata"); const T p3 = j.template get(); CHECK(p3.getName() == ""); CHECK(p3.getAge() == 0); CHECK(p3.getMetadata() == nullptr); // check default value in case of empty json const Json j4; const T p4 = j4.template get(); CHECK(p4.getName() == ""); CHECK(p4.getAge() == 0); CHECK(p4.getMetadata() == nullptr); } } TEST_CASE_TEMPLATE("Serialization/deserialization via NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_WITH_DEFAULT and NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_WITH_DEFAULT", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; constexpr bool is_ordered = std::is_same::value; SECTION("derived person with default values") { // serialization of default constructed object const T p0{}; CHECK(Json(p0).dump() == (is_ordered ? R"({"age":0,"name":"","metadata":null,"hair_color":"blue"})" : R"({"age":0,"hair_color":"blue","metadata":null,"name":""})")); // serialization T p1("Erik", 1, {{"haircuts", 2}}, "red"); CHECK(Json(p1).dump() == (is_ordered ? R"({"age":1,"name":"Erik","metadata":{"haircuts":2},"hair_color":"red"})" : R"({"age":1,"hair_color":"red","metadata":{"haircuts":2},"name":"Erik"})")); // deserialization auto p2 = Json(p1).template get(); CHECK(p2 == p1); // roundtrip CHECK(T(Json(p1)) == p1); CHECK(Json(T(Json(p1))) == Json(p1)); // check default value in case of missing field Json j = Json(p1); j.erase("name"); j.erase("age"); j.erase("metadata"); j.erase("hair_color"); const T p3 = j.template get(); CHECK(p3.getName() == ""); CHECK(p3.getAge() == 0); CHECK(p3.getMetadata() == nullptr); CHECK(p3.getHairColor() == "blue"); } } TEST_CASE_TEMPLATE("Serialization/deserialization of classes with 26 public/private member variables via NLOHMANN_DEFINE_TYPE_INTRUSIVE and NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; SECTION("alphabet") { T obj1; Json const j = obj1; T obj2; j.get_to(obj2); CHECK(obj1 == obj2); } } TEST_CASE_TEMPLATE("Serialization of non-default-constructible classes via NLOHMANN_DEFINE_TYPE_INTRUSIVE_ONLY_SERIALIZE and NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; constexpr bool is_ordered = std::is_same::value; SECTION("person") { // serialization of a single object const T person{"Erik", 1}; CHECK(Json(person).dump() == (is_ordered ? R"({"name":"Erik","age":1})" : R"({"age":1,"name":"Erik"})")); // serialization of a container with objects std::vector const two_persons { {"Erik", 1}, {"Kyle", 2} }; CHECK(Json(two_persons).dump() == (is_ordered ? R"([{"name":"Erik","age":1},{"name":"Kyle","age":2}])" : R"([{"age":1,"name":"Erik"},{"age":2,"name":"Kyle"}])")); } } TEST_CASE_TEMPLATE("Serialization of non-default-constructible classes via NLOHMANN_DEFINE_DERIVED_TYPE_INTRUSIVE_ONLY_SERIALIZE and NLOHMANN_DEFINE_DERIVED_TYPE_NON_INTRUSIVE_ONLY_SERIALIZE", Pair, // NOLINT(readability-math-missing-parentheses) std::pair, std::pair, std::pair, std::pair) { using Json = typename Pair::first_type; using T = typename Pair::second_type; constexpr bool is_ordered = std::is_same::value; SECTION("derived person only serialize") { // serialization of a single object const T person{"Erik", 1, "brown"}; CHECK(Json(person).dump() == (is_ordered ? R"({"name":"Erik","age":1,"hair_color":"brown"})" : R"({"age":1,"hair_color":"brown","name":"Erik"})")); // serialization of a container with objects std::vector const two_persons { {"Erik", 1, "brown"}, {"Kyle", 2, "black"} }; CHECK(Json(two_persons).dump() == (is_ordered ? R"([{"name":"Erik","age":1,"hair_color":"brown"},{"name":"Kyle","age":2,"hair_color":"black"}])" : R"([{"age":1,"hair_color":"brown","name":"Erik"},{"age":2,"hair_color":"black","name":"Kyle"}])")); } }